Wet process for a continuous length of moving material

ABSTRACT

A PROCESS FOR SUBJECTING A CONTINUOUS LENGTH OF MOVING MATERIAL TO A LIQUID TREATMENT. THE MATERIAL IS INITIALLY SOAKED IN A BATH OF PROCESSING LIQUID WHILE IN A SUBSTANTIALLY TENSIONLESS CONDITION. IMMEDIATLEY THEREAFTER, THE MATERIAL IS GUIDED THROUGH A TREATMENT CHAMBER WHERE   IT IS EXPOSED TO A HIGH VELOCITY OF FLOW OF THE SAME PROCESSING LIQUID.

F. PETER July-18, 1972- WET PROCESS FOR A CONTINUOUS LENGTH OF MOVINGMATERIAL Original Filed June 19 1968 3 Sheets-Sheet l F. PETER July 1 8,1972 WET PROCESS FOR A CONTINUOUS LENGTH OF MOVING MATERIAL 3Sheets-Sheet 2 Original Filed June 19, 1968 Eda/w F. PETER 3,677,695

WET PROCESS FOR A CONTINUOUS LENGTH OF MOVING MATERIAL July 13, 1972 3Sheets-Sheet 5 Original Filed June 19, 1968 United States Patent ice3,677,695 WET PROCESS FOR A CONTINUOUS LENGTH OF MOVING MATERIAL FritzPeter, 124 Howe Ava, Shrewsbury, Mass. @1545 Application June 19, 1968,Ser. No. 747,409, which is a continuation-in-part of application Ser.No. 657,632, Aug. 1, 1967. Divided and this application Apr. 23, 1970,Ser. No. 43,237

Int. Cl. Bc 3/05, 3/52, 3/170 US. Cl. 8-152 4 Claims ABSTRACT OF THEDISCLOSURE A process for subjecting a continuous length of movingmaterial to a liquid treatment. The material is initially soaked in abath of processing liquid while in a substantially tensionlesscondition. Immediately thereafter, the material is guided through atreatment chamber where it is exposed to a high velocity flow of thesame processing liquid.

SUMMARY OF THE INVENTION This application is a divisional applicationbased on U.S. application Ser. No. 747,409 filed June 19, 1968 (nowabandoned), the latter being a continuation-in-part of US. patentapplication Ser. No. 657,632, filed Aug. 1, 1967 (also abandoned.) Indescribing the invention, reference will hereinafter be made to thetreatment of web material in the textile industry. It is to beunderstood, however, that this particular industrial application isbeing used for illustrative purposes only and is not to be considered asa limitation upon the scope of the claims appended hereto.

In the textile industry, continuous lengths of fabric (often in webform) are subjected to various continuous wet finishing processes suchas for example dyeing, bleaching, washing, etc. It has now beendiscovered that the efficiency of many of these processes can bematerially improved by subdividing each treatment into the following twobasic steps: (1) soaking the web material for a predetermined timeinterval in a bath of the processing liquid. While soaking in theliquid, the material is maintained in a relaxed substantiallytensionless condition; (2) immediately thereafter subjecting thematerial to one or more high velocity streams of processing liquid.herein employed, the term high velocity is intended to include liquidvelocities of at least six feet per second and greater, preferably inthe range of approximately fifteen feet per second.

By initially soaking the web material in a relaxed tensionlesscondition, an advantage is gained in that penetration of the processingliquid between the fibers making up the web material is greatlyfacilitated. In certain operations such as dyeing, complete penetrationof the dye liquor is of course highly desirable. By the same token, whenwashing a cloth web, penetration of the processing liquid between therelaxed fibers aids in dissolving particles, as well as in dislodginginsoluble particles that might otherwise remain wedged between thefibers.

Subjecting the material to a high velocity stream of processing liquidimmediately after the soaking period further improves the etficiency ofthe operation by providing a second opportunity for liquid penetrationbetween the fabric fibers. Also, in a washing operation, this secondstep effectively flushes out partially dissolved soluble particles andany insoluble particles such as for example loose fibers, dirt, dyepigments, oil, etc., previously dislodged or loosened during the soakingperiod. Where insoluble particles are particularly troublesome, thetreatment chamber may be provided with additional means for mechanicallyflexing and gently beating the material 3,677,695 Patented July 18, 1972while it is being exposed to the high velocity flow of processing liquidso as to work any trapped particles free from between adjacent fibers.This alternate embodiment of the treatment chamber is more fullydescribed in a copending application of the present inventor entitledWet Processing Apparatus, U.S. Ser. No. 657,702, filed Aug. 1, 1967, nowPat. No. 3,430,466.

In light of the foregoing, it is a general object of the presentinvention to provide an improved wet process for continuous lengths ofmaterial such as for example cloth webs.

Another object of the present invention is to provide a wet process forcontinuous lengths of material which includes the steps of (1) soakingthe material in the processing liquid in a relaxed substantiallytensionless condition; and (2) immediately thereafter subjecting thematerial to at least one high velocity stream of processing liquid.

These and other objects of the present invention will become moreapparent as the description proceeds with the aid of the accompanyingdrawings of which:

FIG. 1 is a generally cross-sectional view of one embodiment of anapparatus employed in the practice of the present invention;

FIG. 2 is an enlarged cross-sectional view of the treatment chambershown in FIG. 1;

FIG. 3 is a cross-sectional view of an alternate embodiment of thetreatment chamber equipped with a vibrating reed member;

FIG. 4 is an enlarged cross-sectional view of a portion of the treatmentchamber shown in FIG. 3, and

FIG. 5 is a generally cross-sectional view similar to FIG. 1 showing analternate embodiment of the means employed to feed the web material intothe apparatus.

Referring initially to FIGS. 1 and 2 wherein are best shown generalfeatures of one embodiment of an apparatus employed in practicing thepresent invention, a tank generally indicated by the reference numeral10 is shown filled with processing liquid 11 to a level indicated at 12.The level 12 of the processing liquid may be controlled by feeding moreliquid into the tank through feed valve 14, or draining liquid out ofthe tank through drain valve 16. A curved baffle member 18 cooperateswith the tank walls in defining a soaking area hereinafter referred toas a scray 20. The scray provides an in-process storage area in whichthe processing liquid can react for a predetermined time interval withthe material being treated.

The material to be treated, herein schematically illustrated as a clothweb 22, is fed into the scray 20 by any known means, such as for examplea pair of feed rolls 24. As the cloth web leaves the feed rolls, it isdeposited in the scray 20 in the form of substantially tensionlessrelaxed folds indicated typically by the reference numerals 26. Afterthe web material has soaked in the scray 20 in a relaxed condition for apredetermined period of time, it is guided around an idler roll 28upwardly to a treatment chamber generally indicated by the referencenumeral 30.

The time period during which the web material 22 will be allowed to soakin the scray 20 will depend primarily on the number of folds 26 allowedto accumulate therein. Thus, where a longer soak. is required, a greateramount of material will be accumulated in the form of relaxed folds 26.

As can be best seen by reference to FIG. 2, treatment chamber 30includes two mating sections 32a and 32b which cooperate to define aninner cylindrical cavity 34. Cavity 34 is in turn connected by means ofan intermediate treatment zone 36 which as herein shown may include adivergent exit area 38 facing downwardly towards the interior of tank10. Spaced small diameter rollers 42a, 42b, 43a and 43b are rotatablymounted within cavity 34. The web material passes upwardly throughtreatment zone 36 where it enters cavity 34. At this point, the materialis threaded in a somewhat triangular path between rollers 42a and 4211,over rollers 43b and 43a, and then back down between the lower rollers42a and 42b. From this point, the material passes back downwardlythrough treatment zone 36, where it exits from the treatment chamber.The material continues to travel downwardly beneath the level 12 ofprocessing liquid 11, around another submerged idler 44, and thenupwardly again to a second set of driven nip rolls 46 which pull thecloth to the next processing step. The fresh processing liquid enteringthrough feed valve 14 may be sprayed by means of a series of nozzles 47directly onto the web immediately prior to its passing between niprollers 46, thus providing a terminal wash effect.

A flow of processing liquid is pumped from tank to treatment chamber 30by means of a pump 48 and its associated suction and delivery piping 50and 52. The processing liquid enters from cavity 34 of treatment chamber30 from the side through a passageway 54 (see FIGS. 2 and 3). The volumeof liquid being delivered by pump 48 is such that cavity 34 is filledwith processing liquid under pressure. The processing liquid exits fromcavity 34 as a high velocity stream flowing downwardly through treatmentzone '36. After emerging from the treatment chamber, the stream ofprocessing liquid simply drops back into tank 10.

[In view of the foregoing, it can be seen that after having been soakedin a relaxed substantially tensionless condition in the scray 20, thematerial is immediately guided through treatment chamber 30. Whilepassing through the treatment chamber and particularly while travelingthrough treatment zone 36, the material is exposed to a high velocitystream of processing liquid exiting from cavity 34. This stream travelsin a direction substantially parallel to the direction in which thecloth is moving, and in a direction opposite to that of the materialmoving upwardly through treatment zone 36 into cavity 34.

By exposing the material to a high velocity stream of processing liquidimmediately after the soaking step, a flushing action is created whichaids in dislodging partially dissolved soluble particles and insolubleparticles embedded in the web. This flushing action is aided by thefabric being bent and flexed as it passes around rollers 42a, 42b and43a and 43b. The liquid pressure in cavity 84 and treatment zone 36 alsoencourages penetration of the treatment liquid through the fibers of thefabric.

As previously mentioned, there may be instances where .the removal ofpartially dissolved soluble particles and insoluble particles frombetween web fibers becomes particularly troublesome. Under suchconditions, it may be desirable to modify the treatment chamber 30 alongthe lines more fully described and claimed in the above referred topatent of the present inventor. As shown in FIGS. 3 and 4, one suchmodification might include the mounting of a reed member 56 on a support58 underlying the treatment chamber 30. Preferably, reed member 56 ispositioned to extend upwardly between the outwardly sloping wallportions 60a and 60b defining the divergent area 38 of treatment zone36.

As the high velocity stream of processing liquid flows downwardlybetween the spaced opposed parallel wall portions 62a and 62b oftreatment zone 36, some turbulence is experienced, particularly in thearea adjacent the shoulders 64 formed between the parallel wall portions62a and 62b and the continuing diverging wall portions 601: and 60b (seeFIG. 4). This turbulence causes the upper end of reed member 56 tovibrate laterally between wall portions 62a and 62b. In (FIG. 4, thereed member 56 is shown in solid lines in its neutral position. Theextremes to which the reed member will be caused to later- 4 allyvibrate are indicated in dotted lines as at 56a and 56b.

By causing the reed member 56 to vibrate as shown in FIG. 4, thematerial running through treatment zone 36 is gently beaten andlaterally flexed. For example, in FIG. 3, the reed member is shownflexed to one extreme position, with its upper end pressing thedownwardly moving web material against wall portion 62a. When derflectedto this position, the reed also momentarily cuts of the flow ofprocessing liquid to the side 66 of divergent area 38, whilesimultaneously directing the entire stream of processing liquid towardswall portion 60b and into the side 68 of area 38. Although at thisstage, flow of processing liquid to side 66 is instantaneously cut oif,the liquid already in this area continues to move downwardly due to itsown inertia, thus producing a cavitational effect which results in thedownwardly moving web material 22 being exposed to a condition ofvacuum. At the same time, the upwardly moving Web material to the leftside 68 of reed member 56 is exposed to the full velocity, turbulenceand pressure of the exiting stream of processing liquid. It cantherefore be seen that at the point illustrated in FIG. 3, the upper endof reed member 56 has contacted and laterally flexed the downwardlymoving web material 22 to the right. This results in the followingactions occur-ring simultaneously: (a) the downwardly moving material isgently beaten against wall portion 62a; (b) the downwardly movingmaterial in area 66 is exposed to a condition of vacuum; and (c) theupwardly moving material to the left of reed member 56 is exposed to thefull velocity and effect of the exiting stream of processing liquid.

When reed member 56 vibrates to the other extreme ,(as shown at 56b inFIG. 4 the opposite result will be obtained. That is to say, theupwardly moving material will now be laterally flexed and beaten againstwall portion 62b. A cavitational effect will be created in area 68 whileat the same time, the full force and effect of the exiting stream ofprocessing liquid will be deflected to the right towards Wall portions62a and 60a.

To illustrate the efficiencies capable of being obtained with theabove-described process, a test sample of print cloth x 80 threads persq. inch, 4 yards per lb.) was impregnated with a caustic soda solutionof 6% concentration. The test sample was sewn into a continuous web ofmaterial which was then run once through the apparatus illustrated inFIG. 1 at a speed of about yards per minute. Dwell time in the scray wasapproximately 12.5 seconds. The processing liquid, in this case water atEv, was pumped through the treatment chamber, the volume beingsufiicient to maintain a pressure of approximately 2 to 2.5 psi. in thecavity 34. This produced a liquid velocity in treatment zone 36 ofapproximately fifteen feet/ second. Without a reed member 56 installedin the treatment chamber, the process succeeded in removing 94.6% of thecaustic soda impregnated in the test sample. The addition of thevibrating reed member 56 under the same operating conditions resulted ina still higher efliciency of 95.7% caustic soda removal. Theseefiiciences are substantially above those capable of being achieved withconventional processes and apparatus operating under substantiallysimilar conditions. To illustrate this point, in one experiment, thematerial was run through the apparatus without providing for a dwelltime in the scray 20 and without a reed member 56 in the treatmentchamber 30. Under these conditions, only 89.5% of the casustic soda wasremoved from the cloth sample. In another experiment, flow of liquid tothe treatment chamber 30 was cut off, thus relying solely on the soakingtime in the scray 20. This resulted in only 89.4% of the caustic sodabeing removed from the test sample.

In view of the foregoing, it can readily be seen that much higherelficiencies are obtained by employing a twostep process which includesa dwell time during which the material is soaked in a relaxedsubstantially tensionless condition, followed immediately by a flushingaction achieved by exposing the material to a high velocity stream ofliquid. A still higher efliciency is made possible by mechanicallyflexing and gently beating the material while it is being exposed tohigh velocity stream of liquid.

An alternate arrangement for feeding web material into the apparatus isshown in FIG. 5. In this embodiment, two slanted interior wall members70 and 72 are spaced to define a storage area 74. The incoming Webmaterial 22 is passed initially over guide roll 76, then downwardly intoa bath of processing liquid 77 around roll 78 before being pulledupwardly through the nip 80 of rolls 82 and 84. Either roll 82 or 84 maybe driven by conventional means Doctor blades 85 prevent the webmaterial from wrapping around the rolls '82 and 84. After exiting fromnip 80, the web material accumulates and soaks in the lower portion ofstorage area 74, in the form of relaxed tensionless folds 86. The numberof folds 86 which are allowed to accumulate will be governed by thesoaking time desired for a particular operation. From storage area 74,the web material is pulled upwardly out of the processing fluid and overguide roll 88, then downwardly around submerged guide roll 90, and thenupwardly into a treatment chamber 30 of the type shown in either FIG. 1or FIGS. 2-4. From this point on, the web material is treated in amanner identical to that described above.

This alternate embodiment is particularly suited for application wherethe web material has a tendency to float on the surface of theprocessing liquid. Under such circumstances, it may be advantageous topull the material downwardly into the bath of processing liquid beforereleasing it for soaking in the form of relaxed tensionless folds 86 inthe storage area 74.

It is my intention to cover all changes and modifications of theembodiments herein chosen for purposes of disclosure which do notconstitute departures from the spirit and scope of the invention.

I claim:

1. A wet process for a continuous length of moving material comprisingthe steps of: conveying the material through a bath of processingliquid, the material being in a relaxed substantially tensionlesscondition while in said bath; guiding the material out of said bath andthrough a treatment chamber, the said chamber also having a flow of saidprocessing liquid circulating therethrough, and, subjecting the materialentering and exiting from said chamber to a mechanical beating action.

2. The process as claimed in claim 1 wherein the material is caused toenter and exit from said chamber through an opening which also serves asthe outlet for the flow of processing liquid being circulated throughsaid chamber.

3. The process as claimed in claim 2 wherein the said mechanical beatingaction is accompanied by the alternate exposure of said material to highvelocity liquid -fiow and vacuum.

4. A wet process for a continuous length of moving material comprising:conveying the material through a bath of processing liquid; pumpingprocessing liquid from said bath into a treatment chamber, theprocessing liquid being thereafter allowed to exit through an opening insaid chamber and to return to said bath; guiding the material out ofsaid bath and into and out of said chamber through said opening; andsubjecting the material entering and exiting from said chamber to amechanical beating action.

References Cited UNITED STATES PATENTS 1,062,245 5/1913 Mathesius et a1.68-479 X 1,913,601 6/1933 Leppin 68-62 FOREIGN PATENTS 6,871 1906 GreatBritain 68---l78 WILLIAM I. TRICE, Primary Examiner US. Cl. X.R. 8-4 58

